Aaron Price, Far East correspondent for the British Times, investigates the true identity of Lieutenant colonel Yuuki, the man rumored to have founded D-Agency. Flipping through the Military Preparatory School's list of past enrollees, his eye is drawn to a boy who passed the entrance exam at the top of his class, but was expelled for violence. His name? Akira Arisaki.
Taking place in the year 1937 on the eve of World War II, the story involves a mysterious spy training organization known as the "D Agency." The organization is established by Lieutenant Colonel Yuuki from the Imperial Japanese Army. His ideals lead him to recruit people beyond military academy graduates and personnel, while training them to become skilled agents in arts of manipulation. These agents would become a specialized team to conduct operations. One such antihero agent, under the name Jirou Gamou, goes on a harrowing mission to uncover secret documents titled "Black Notes," while battling forces from within and without his own ranks.
